An Online charging system (OCS) is a system allowing communication service providers of telecommunications networks (GSM, CDMA, WCDMA, etc.) to charge perpaid and postpaid subscribers, in real time, based on service usage. Charging transactions are made in real time, meaning that funds are reserved on a subscriber's account before a service is delivered and new funds may be reserved continuously. This ensures that services are only provided if there are funds to cover for them. Naturally OCS allows for a subscriber to have multiple communication sessions open simultaneously while maintaining control of the account balance. Support for customer interaction and notifications may be provided to make it easy for subscribers to keep continuous track of their spending. Hence, the combination of rating, cost determining unit and database may be referred as an Online Charging System (OCS).
Telecom operators are facing new demands on charging of real-time services in addition to existing charging and rating methods. A service, such as a phone call, is charged according the consumers rates and to the consumers account. According to another scenario a consumer rate plan is used in combination with a fund provider account. This could be a family account where the child has access to an account belonging to the parent but all the rating is done according to the child's rates. In another case a company has negotiated a special rate for all its employees but the employees has to pay for the calls them selves, i.e a fund provider rate plan is used while charging consumer accounts. According to a common scenario for companies is when a fund provider rate plan is used for charging the fund provider account. In this case, all charges done by an employee is charged according to the rates for the company and to the company account.
In large systems subscriber information is spread over several systems or centrally stored in a data base. To be able to perform operations on the data, it is in many cases necessary to transport the information from one system to another or from a data base to a system that will perform operations on it.
In charging and rating scenarios this is most obvious when one subscriber has access to another subscriber's information. This is used when one subscriber for instance has access to the possibility to let another subscriber take the charges for a call. In telecommunication and interne solutions the main protocol used for rating requests is Diameter. If the subscribers reside in the same database and is processed by the rating and cost determining unit it is not an issue, but if they are stored on different databases or are rated by separate rating processing units then one subscriber needs some manner to interact with the other.
Charging and rating scenarios when one subscriber has access to another subscriber's information may involve one or more consumers and fund providers. In this context, a consumer is an individual that may use a service and has an account, i.e a subscriber with an account. A fund provider is an individual or company that has an account that may be used by one or more consumers. A rate plan is a product that a consumer or fund provider must purchase in order to get access to any service, which may be a combination of a service class and tariff tree.
Telecom operators are facing new demands on charging of real-time services in addition to existing charging and rating methods. The most common case is when a service, such as a phone call, is charged according the consumers rates and to the consumers account. According to another scenario a consumer rate plan is used in combination with a fund provider account. This could be a family account where the child has access to an account belonging to the parent but all the rating is done according to the child's rates. In another case a company has negotiated a special rate for all its employees but the employees has to pay for the calls them selves, i.e a fund provider rate plan is used when charging consumer accounts. According to a common scenario for companies is when a fund provider rate plan is used for charging the fund provider account. In this case, all charges done by an employee is charged according to the rates for the company and to the company account.
A problem associated with requesting information from one Online Charging System (OCS) to another is that the information received will be limited by the functionality that can be provided by the protocol used and the frequency in the updates between the subscribers.
For example, a first subscriber has an account on a first OCS, but also the option to charge a second subscriber with an account on a second OCS for part or all of a service offered. If the first subscriber would send the request for charges over to the second OCS holding the second subscriber and if then the second subscriber only agreed to pay for a part, e.g. the first part of the charge, the request would have to be dropped back to first subscriber again. The first subscriber would then have to evaluate this further to check how the rest of the charge should be paid. It may come to the conclusion that it will take charge for a part of the charge, e.g the second part, but the rest is again to be handled by the second subscriber. If the service can be split into several parts that will be divided between the two subscribers this will be very protocol intensive, i.e a lot of subscriber information has to be transmitted back and forth between the first and second OCSs.
To meet these challenges an efficient shared charging and rating for service usage is desired.